The present invention relates to attachments for stringed instruments and pertains particularly to an improved capo for fretted stringed instruments.
It is frequently desirable to raise the pitch of the strings of fretted stringed musical instruments. This is typically accomplished by means of a device called a capotasto, usually referred to as a capo. A capo is typically a device which is clamped across the strings for pulling and clamping the strings to the frets which are embedded in the finger board or neck of the instruments. This shortens the effective vibrating length of the strings, and thereby raises the pitch thereof.
The prior art capos typically employ a straight rigid bar for extending across the strings, with a strap extending behind the neck of the instrument for securing the bar in place. The bar is moved to various fret locations along the finger board for selectively raising the pitch of the instrument. Relatively large forces are required to simultaneously clamp all strings with a straight rigid bar due to the adverse profile imposed by the tops of the strings. Several devices have been devised to increase the clamping force to effectively clamp the strings to the frets. These, however, tend to be unwieldy and unreliable, and require unusual manual dexterity to use. These prior art devices must be removed or loosened to change position along the finger board and then re-tightened. When not in use, they are typically removed from the instrument and temporarily stored.
In my prior application, I disclose an improved capo having a spring bar that deflected and progressively applied pressure to the strings to bias them into engagement with the frets. The bar included variations in the cross sectional configuration to vary the stiffness of the bar along the length thereof. The application also disclosed improved sheaths for the capo. I have discovered further improvements in bar configuration and sheaths that are incorporated herein.
It is desirable that the capo be capable of biasing all of the strings uniformly into engagement with the frets, and be simple and easy to move to selective locations along the neck of the instrument.